3 years ago

Question 8 of 16

Physics

1 answer:

Korolek [52]3 years ago

5 0

Answer:

Explanation:

PE = mgh where m is the mass, g is gravity, and h is the height from which the object can potentially fall. We are given enough info here to solve for h. Filling in:

42 = 1.8(9.8)h and

$h=\frac{42}{(1.8)(9.8)}$ and rounding to 2 sig fig's as we need:

h = 2.4 m, choice D

You might be interested in

A car brakes from 25 m/s to 16 m/s in 2.0s. what is its acceleration?<br>

Mars2501 [29]

Acceleration = (16-25) / 2 = - 4.5 m/s^2

3 0

3 years ago

________________________ is the use of circuitry to manipulate the transfer of electrical energy by controlling the closed path.

Alekssandra [29.7K]

Answer:

switch

Explanation:

5 0

3 years ago

How long it take a train to cover 630km having a speed of 30 km/hr

noname [10]

Answer:

21 hours

Explanation:

well 30 x 20 = 600 than 21 = 630

4 0

3 years ago

When a volume stress is applied to a rigid body and the stress is small enough such that the object returns to its original shap

lara [203]

IDK sorry girl ಥ‿ಥ I wish I can help

6 0

3 years ago

A 1,250 W electric motor is connected to a 220 Vrms, 60 Hz source. The power factor is lagging by 0.65. To correct the pf to 0.9

Black_prince [1.1K]

Answer:

$C = 46.891 \mu F$

Explanation:

Given data:

v = 220 rms

power factor = 0.65

P = 1250 W

New power factor is 0.9 lag

we knwo that

$s = \frac{P}{P.F} < COS^{-1} 0.65$

$S = \frac{1250}{0.65} < 49.45$

s = 1923.09 < 49.65^o

s = [1250 + 1461 j] vA

$P.F new = cos [tan^{-1} \frac{Q_{new}}{P}]$

solving for $Q_{new}$

$Q_{new} = P tan [cos^{-1} P.F new]$

$Q_{new} = 1250 [tan[cos^{-1}0.9]]$

$Q_{new} = 605.40 VARS$

$Q_C = Q - Q_{new}$

$Q_C = 1461 - 605.4 = 855.6 vars$

$Q_C = \frac[v_{rms}^2}{xc} =v_{rms}^2 \omega C$

$C = \frac{Q_C}{ v_{rms}^2 \omega}$

$C = \frac{855.6}{220^2 \times 2\pi \times 60}$

$C = 4..689 \times 10^{-5}$ Faraday

$C = 46.891 \mu F$

6 0

4 years ago